Hasil Pencarian  ::  Simpan CSV :: Kembali

"Tahap eksplorasi pada pengembangan lapangan geotermal merupakan tahap yang paling penting untuk memahami sistim geotermal. Pemahaman sistim geotermal yang baik dapat meminimalkan risiko kegagalan pada saat pemboran sumur produksi dilakukan. Eksplorasi geofisika yang digunakan penelitian ini adalah metode gravitasi. Metode gravitasi pada prinsipnya mengidentifikasi variasi densitas pada bawah permukaan sehingga dapat digunakan untuk delineasi struktur bawah permukaan. Kombinasi antara metode upward continuation dan second vertical derivative dilakukan untuk mengkarakterisasi struktur geologi baik arah kemiringan, perkiraan kedalaman, perkiraan sudut kemiringan dan jenis struktur. Hasil ML-SVD menunjukan bahwa karakteristik struktur geologi daerah penelitian memiliki dip >60°, terdapat patahan normal maupun reverse dan mampu mengidentifikasi struktur pada kedalaman tertentu. Terdapat pola struktur melingkar yang didugga berasosiasi dengan kaldera Pangkalan. Pemodelan data gravitasi 2D dilakukan untuk mengetahui sebaran densitas bawah permukaan. Pemodelan densitas menunjukan bahwa densitas lapisan clay cap sebesar 2,28 g/cc dan lapisan reservoir sebesar 2,55 g/cc. Analisa geokimia gas menunjukan temperatur rata-rata reservoir sebesar 253 ºC. Zona upflow daerah penelitian berada didalam struktur melingkar.

---

Exploration stage on geothermal development are the most important stage to understand the geothermal system of research area. A good understanding of geothermal system can minimize the risk of failure in drilling stage. Geophysical exploration method in this research is gravity method. The gravity method in principle identifies density variations below the surface so that it can be used to delineate subsurface structures. The combination of the upward continuation and second vertical derivative methods is carried out to characterize the geological structure both the slope direction, depth estimation, dip estimation and type of structure.

ML-SVD result show that fault structure at research area have value of dip > 60º, fault configuration and depth of fault under rock layers. Fault with circular pattern have been found that expected associate with Pangkalan caldera. 2D density model is done to determinate the distribution of subsurvace density. 2D density model show that clay cap have density value 2.28 g/cc and reservoir 2.55 g/cc. Gas geochemistry analysis show the temperatur at reservoir 253 ºC. The upflow zone estimated inside the circular structure of research area."

"[ABSTRAKAnalisa rock physics dilakukan untuk memberikan gambaran tentang hubunganantara properti fisis batuan dengan respon gelombang seismik yang menjalarmelaluinya. Tesis ini merupakan sebuah studi kasus pada lapangan Rote, yangmembahas tentang pengaplikasian rock physics sebelum melakukan karakterisasireservoar dengan metode inversi simultan untuk mendapatkan informasi sebaranlitologi dan fluida. Hasil pemodelan AVO menunjukan bahwa nilai gradienamplitudo dari reservoar dengan saturasi hidrokarbon gas lebih tinggi daripadareservoar dengan saturasi minyak. Analisa sensitivitas pada data sumurmenunjukan bahwa atribut impedansi akustik dan terutama VP/VS dapatdigunakan untuk identifikasi litologi, sedangkan identifikasi fluida sulit dilakukankarena separasi yang minim. Hasil inversi atribut VP/VS kemudian digunakanuntuk mendeliniasikan persebaran reservoar (nilai VP/VS rendah).

---

ABSTRACTRock physics analysis is performed in aim to describe the relationship betweenrock physical property and seismic wave response which travels through it. Thisthesis is a case study done in Rote field, which discuss the application of rockphysics prior to characterizing the reservoir with simultaneous inversion to obtainlithology distribution as well as fluid prediction. AVO modeling results showsthat the amplitude gradient of the gas saturated reservoir yields higher valuescompared to the brine saturated reservoir. Sensitivity analysis at wells shows thatthe acoustic impedance and mainly VP/VS are useful attributes to be used inidentifying lithologies, meanwhile fluid discrimination is difficult to be performedas the separation is minimal. The VPVS ratio attribute was then used to delineatereservoir distribution., Rock physics analysis is performed in aim to describe the relationship betweenrock physical property and seismic wave response which travels through it. Thisthesis is a case study done in Rote field, which discuss the application of rockphysics prior to characterizing the reservoir with simultaneous inversion to obtainlithology distribution as well as fluid prediction. AVO modeling results showsthat the amplitude gradient of the gas saturated reservoir yields higher valuescompared to the brine saturated reservoir. Sensitivity analysis at wells shows thatthe acoustic impedance and mainly VP/VS are useful attributes to be used inidentifying lithologies, meanwhile fluid discrimination is difficult to be performedas the separation is minimal. The VPVS ratio attribute was then used to delineatereservoir distribution.]"

"The subject of this book is the methodology and results of integrated geophysical investigations in the Caucasian region, mainly interpretation of magnetic and gravity anomalies with utilization of a huge petrophysical database for the evaluation of geological structure and mineral resources. Numerous illustrations (including colour) elucidate different problems and solutions on various scales and in diverse geological-geophysical environments."